Features
- Reduction of the repetition rate of mode-locked lasers
- Low dispersion
- Suitable for fs and ps mode-locked lasers
- Division ratios down to fREP/2 (optional)
Overview
The pulseSelect has been developed for the special demands of femtosecond or picosecond laser technology. Pulse distortion is minimized by a low dispersive design and the use of reflective optics. The use of an acousto-optical selection element allows for high repetition rates and high contrast ratio.
The pulseSelect Dual is a single pulse selector using two acousto-optical Bragg cells.
The pulseSelect Dual comes in two variants:
pulseSelect Dual (serial)
This version is designed to allow for highest contrast ratio of above 6000:1 by placing two Bragg cells, both synchronized to common clock, in serial configuration (i.e. one beam through two Bragg cells).
pulseSelect Dual parallel
This version is designed for selecting pulses from two synchronized laser sources simultaneously by placing two Bragg cells, both synchronized to one common clock with one common division ratio but independent delay settings, in parallel configuration (i.e. two separate beams each through one Bragg cell).
Specifications
Standard | HP-Ti:Sa | HP-Ti:Sa Dualband | |
Wavelength | 500 … 1600 nm | 680 … 1080 nm | 680 … 1080 nm and 340 … 540 nm |
Max. input power (PAV) | < 2 W (SiO2)1) | < 5 W (SiO2)1) | < 5 W (SiO2)1) |
Input frequency | 70 … 85 MHz (others on request) | ||
(to be specified with ± 0.5 MHz accuracy at time of order) | |||
External trigger | single shot to 3 MHz input | ||
Input polarization | linear / horizontal (polarization rotator optional) | ||
Division ratio | fREP/20 … fREP/5000 | ||
(fREP/2 … fREP/260000 optional) | |||
or externally triggered | |||
pulseSelect Dual (serial): | pulseSelect Dual parallel: | ||
Diffraction efficiency | approx. 25% (SiO2)2) | > 50 % (SiO2)2)3) | |
approx. 36% (TeO2)2) | > 60 % (TeO2)2)3) | ||
Contrast ratio | > 6000:14) | > 500:15) |
1) These values depend on the laser spot diameter in the crystal or mirror coating and for the type of Bragg cell indicated and thus apply only for a certain system configuration. Please consult our technical staff to determine the maximum input power level as well as the appropriate focussing for the beam parameters applicable for your laser system setup.
2) Ratio of the diffracted pulse energy to the pulse energy incident into Bragg cell. Measured at 800 nm and division ratio fREP/20.
3) At division ratio fREP/2 the efficiency is typically around 25 % (TeO2 Bragg cell) and around 10 % (SiO2 Bragg cell), respectively.
4) Main pulse to adjacent pulse contrast ratio is > 6000:1 (@ 800 nm fREP/20)
5) > 500:1 applies for non-adjacent pulses. Main pulse to adjacent pulse contrast ratio is > 75:1 (@ 800 nm fREP/20)
Literature
A publication mentioning the use of the pulseSelect Dual:
Lane, Two-photon excitation of the fluorescent nucleobase analogues 2-AP and tC,
RSC Advances, Issue 30, 11397-11403 (2012), Link (DOI) | Link